[Cushing syndrome after steroid-infiltration in two HIV-patients with antiretroviral therapy].

The introduction of antiretroviral treatment with at least three active drugs has caused a substantial reduction of morbidity and mortality. Some antiretroviral drugs have the potential of interactions with other drugs. With the so called <<boosted>> protease inhibitors the cytochrom-P450 inhibition by Ritonavir is used to increase the plasma level of the protease inhibitor. This strategy results in prolonged dosage intervals and reduced tablet intake due to a reduced overall dose that is needed. The interaction potential of Ritonavir originates from this cytochrom P450-inhibition. All drugs that are CYP450-metabolized can potentially be affected. Here we report two cases that were affected by the little-known interaction of Ritonavir and Triamcinolonacetonide. In both cases, Cushing symptoms emerged after infiltrations with this steroid drug in usual doses. Here we want to emphasize on this rarely encountered but potentially serious drug-drug interaction potential that is not well known to date. When initiating any new drug in HIV-Patients under antiretroviral treatment, potential interactions should be checked. The Website www.hiv-druginteractions.org is a very useful instrument for this purpose.